Hydraulically-actuated divisible-wedge log-splitter



n 1 D. VORKOEPER ETAL 3, 3 0

HYDRAULICALLY-ACTUATED DI VISIBLE-WEDGE LOG-SPLITTER 2 Sheets-Sheet 2 Filed Aug. 12, 1960 I/VVENTO/PS DPV/6H7' H VOR/(OEPER BY MORROUGH OER/EN 3,d38,51il Patented June 12, 1962 3,038,510 HYDRAULItIALLY-ACTUATED DIVISIBLE- WEDGE LOG-FsPLITTER Dwight Vorkoeper, 143 York Ave., and Morrough QBrien, 643 Qragmont Ave, both of Berkeley, Calif. Filed Aug. 12, 1960, Ser. No. 49,286 2. Claims. (0. 144193) Our invention relates to means primarily useful in the splitting of lumber such as logs, and is designed for individual use in driving asunder adjacent or previously joined members such as the fibres in a log or stump.

An object of the invention is to provide a log splitter which is readily portable by an individual and is useful by him either in the Woods or elsewhere and in connection with logs lying at virtually any attitude, and for the purpose of splitting the logs.

Another object of the invention is to provide a log splitter which is effective upon the application of reasonable manual effort to produce a relatively high force effective to split the desired log.

Another object of the invention is to provide a log splitter which is substantially self-contained and of a simple mechanical nature so that it can readily be used over protracted periods under rugged surroundings.

Another object of the invention is to provide a log splitter which can readily be engaged with virtually any kind of log under virtually any conditions and can serve subsequently to spread apart or to split the log.

Another object of the invention is in general to provide a mechanism for moving materials apart comparable to the splitting of the portions of a log.

An additional object of the invention is in general to provide an improved log splitter.

Other objects, together with the foregoing, are attained in the embodiments of the invention described in the accompanying description and illustrated in the accompanying drawings, in which:

FIGURE 1 is a side elevation of one form of log splitter fabricated pursuant to the invention and in extended position on a split log.

FIGURE 2 is a cross section on an axial plane through the log splitter of FIGURE 1, with the parts in their retracted or compact position.

FIGURE 3 is a detailed section comparable to a portion of FIGURE 2, and showing some of the parts of the hydraulic mechanism in a special location.

FIGURE 4 is an end elevation of the structure shown in FIGURES 1, 2 and 3.

FIGURE 5 is in part a cross section, in part a side elevation and in part a diagram illustrating a modified form of log splitter in its retracted or compact position.

The log splitter pursuant to the invention can be embodied in a number of different variations, depending primarily upon the precise environment in which it is to be utilized, and can take on various configurations and sizes dictated by the precise nature of the work to be accomplished.

Considering first the embodiment disclosed in FIG- URES l to 4 inclusive, there is provided a hydraulic jack 6 including a cylinder 7 and a hollow, cylindrical piston 8. The piston 8 is freely slidable Within the cylinder 7 along an axis 9, being movable to and fro quite freely. The cylinder 7 at one end is preferably closed by a cylinder head 11 conveniently fabricated of a block of metal appropriately secured to the cylinder 7.

A hydraulic pump 12 is incorporated with the cylinder head 11. The pump includes its own barrel 13 with a plunger 14 reciprocable therein. The barrel 13 is preferably screwed into the head 11 and is sealed with a packing ring 16. The plunger 14 has a packing cup 17 at one end thereof, and is also made leakproof by a packing 18 and a packing nut 19 on the barrel 13.

The plunger 14 is connected by a pin 21 to an actuating socket 22, open at both ends. An operating lever 23 is slidably received in the socket, being endwise movable into any selected position and being retained by enlargements 20 and a removable pin 25. The socket 22 is connected by a pivot pin 24 to a link 26, in turn connected to the head 11 by a pivot pin 27 spanning a head recess 28.

For transport, and under various conditions, the handle 23 or lever is retracted through or, after removal of the pin 25, is removed from the socket 22, but in use the lever 23 is inserted firmly into the socket 22 or is projected to its maximum extension so that upon swinging movement of the lever 23 the plunger 14 is easily reciprocated within the barrel 13, this motion being accompanied by slight swinging of the link 26.

The movement of the plunger 14 within the barrel 13 serves to move hydraulic fluid. The piston 8 is tubular and encloses a chamber 31, utilized as a reservoir. Separating the chamber 31 from a chamber 32 within the cylinder 7 is a composite piston head 33, including a plug 34 which is secured within the piston 8 and serves as an anchor for fastenings 36. These secure a packing cup 37 in position through the intermediary of an annulus 38. The packing cup 37 is in part backed up and the piston S is afforded an improved bearing by a band 41 of anti-friction material surrounding and tightly engaging the piston 8 and in sliding engagement with the interior wall of the cylinder 7.

Since the chamber 31 is utilized as a reservoir for hydraulic actuating fluid, a hydraulic feed tube 43 extends into the chamber '31 and to the head 11. The inlet end of the tube 43 adjacent the outboard end of the cylinder 7 is provided with a fitting 44 having an intake pipe 46 projecting downwardly therefrom in the normally utilized attitude of the parts. Hydraulic fluid within the chamber 31 can be Withdrawn from near the bottom of the reservoir. The hollow fitting 44 is preferably threaded onto the end of the tube 43 and can conveniently be oriented in the proper direction upon assembly.

The other end of the intake tube 43 is fastened to a fitting 47 screwed into the head 11 and continuing communication to a passageway 48 in the head 11 and opening into a valve body 49 seated with appropriate gaskets. The valve body 49 is disposed within the same bore in the head 11 that receives the barrel I3 and is clamped in position when the barrel 13 is screwed home. The valve body 49 has a passage 51 alternately opened and closed in accordance with differential pressure upon a ball check 52 serving as an inlet valve. The valve body 9 also has a chamber 53 serving as an outlet under control of a ball check 54 urged toward closed position by a spring 55.

With this arrangement, and considering that the inlet tube 43 is freely open, reciprocation of the lever 23 causes the plunger 14 and barrel 13 with their attendant valves 52 and 54 to act as a force pump, withdrawing hydraulic fluid from the chamber 31 and expelling it under pressure into the chamber 32. This transfer of liquid correspondingly displaces the piston head 33 and the piston 8 along the axis 9 relative to the cylinder 7.

Should the pressure at any time within the chamber 32 become excessive-that is, exceed a predetermined valuerneans are provided for reducing it to a set value. For that reason, intersecting the chamber 53 is a relief passage 61 opening into a bore 62 carrying a relief valve body 63. The body is sealed by a ring 64 and is threadedly engaged with the head 11. At one end 66 the body 63 has a cross bar handle 67 so that the body can be turned until it occupies any desired axial position.

Within the body as is located a relief plunger as urged toward the staked end of the body 63 by a spring as. Also opening into the bore 62 is a second relief passage 71 extending to an annular recess 72 around the body 49 and thus opening into the inlet passageway 48. Thus, when the pressure within the chamber 32, and so upon the plunger 68, is excessive or is suflicient to cause deflection of the spring 69, the needle valve 63 is forced open and excess hydraulic liquid bypasses through the relief passage 71 back to the inlet.

By rotating the body 63 by hand or with a tool, it is possible to set the body in any desired rotated or axial position to aiford the requisite spring pressure so that the desired relief pressure is established. If at any time it is desired to drain the chamber 32 back to the reservoir 31, it is merely necessary to open the valve 68 by withdrawing the body 63, the staked portions of the leading edge of the body carrying the valve 63 to open position.

When the piston head 33 has been sufliciently translated in an expanding direction along the axis 9, it is preferably automatically precluded from travelling farther in the same outward direction. For that reason, the intake tube 43 at a covenient point is provided with an interior sleeve 81 making a reasonably tight fit at its enlarged ends 32 and 83 and having a central bore 84 which continues free communication within the tube 3. However, the sleeve has a reduced peripheral portion to provide an annular recess 86 to establish communication between a pair of apertures 87 and 88 through the tube 43.

When the piston 33 has translated to a position substantially between the openings 87 and 88, there is immediately provided a hydraulic bypass around the piston from the interior of the chamber 32 through the opening 87 and through the annular passage 86 and out the other opening 88 into the chamber 31. This precludes any further addition of hydraulic fluid to the chamber 32 and precludes further translation of the piston, thus serving as a limit stop.

The motion of the piston in one direction (to the right in FIGURE 1) is accompanied by compression of a return spring 91 conveniently disposed Within the hollow piston 8 and at its ends reduced to bear at one end against the piston head 33 and at the other end against the fitting 4-4. Thus as the piston is moved outwardly of the cylinder, the spring 91 is correspondingly compressed. The spring urges the piston back to a nested or compact position within the cylinder, but this cannot be accomplished until such time as the valve 6% is manually opened by rotation of the body 63 to permit return bypass of the hydraulic fluid. There is thus provided a jack mechanism for hydraulically expelling the piston from the cylinder, but only to a certain limit, and a mechanism for restoring the piston to its original posi tion nested within the cylinder.

The jack mechanism is utilized in connection with a separating structure. Firmly mounted on the cylinder 7 is a primary separator 101 extending generally laterally or transversely of the axis on both sides of the cylinder. The primary separator 101 has a tapering extension 162 and is preferably provided on the outer surface with a roughness 103 or scarification. The primary separator has a striking surface 104 conveniently of considerably greater axial extent than the main body of the primary separator itself. The primary separator serves as a mounting for a wiping washer 106 to keep dirt and miscellaneous material which would otherwise adhere to the exposed piston from entering into the cylinder '7.

Firmly fixed on the piston 15 is a secondary separator 167 extending generally transversely or laterally of the axis 9 alongside the primary separator. The extended portion 108 of the secondary separator is contoured very much like that of the primary separator and is conveniently provided also with projections or roughnesses 19%. The extent of the secondary separator 1G7 is such that when nested it fits in and under the striking surface 164 of the primary separator. The piston 8 can rotate in the cylinder 7 and it may sometimes be necessary manually to turn the secondary separator into registry with the primary separator for maximum. piston retraction.

The secondary separator 1117 is provided with a removable filler plug 111 having a washer 112 thereon and affording convenient access to the reservoir 31, so that when the tool is tipped up and the closure 111 is removed, the chain er 31 can be filled (leaving some air space) with hydraulic fluid or, by inversion, hydraulic fluid can be drained therefrom.

In the use of this structure, the parts are positioned especially as shown in FIGURE 2 adjacent a log to be split. With the operating lever 23 out of the way, the primary and secondary separators in nested position can be driven into the log by blows upon the striking surface 194. These blows transmit force to the entire implement and especially tend to distribute the forces about equally to the primary and secondary separators so that they are driven home. If desired the log to be split can be preconditioned by having a saw laerf or the like initially provided therein, and then it is merely necessary to lay the extensions 1132 and 168 into the kerf.

After the log splitter has been so positioned, the operator places the lever 23 in extended position in the socket 22 and manipulates the lever 23 to transfer oil or other hydraulic fluid from the reservoir 31 into the chamber 32. By the exertion of only reasonable manual force, the piston 55 is thus urged to project from the cylinder 7. If the pressure is built up hydraulically to an extent sufficient to open the safety valve 68, the log is not split by the force available but the mechanism is protected. But if there is sufiicient force available before the valve 63 opens, then the primary and secondary separators are urged apart, thus splitting the log. If the log splits far apart, the pressure within the device is abruptly reduced, so that there is no further tendency to spread the primary and secondary separators. If the log at first splits only a short distance and some pressure remains, the spreading motion continues but only until the piston overruns the aperture 87.

After the operation has stopped with the two separators spread apart, the unit is removed from the split log and the body 63 is rotated to permit bypass or return of the hydraulic fluid. The spring 91, in relaxing, restores the parts to their original condition. If the piston has rotated more or less within the cylinder so that the secondary separator does not line up exactly with the primary separator, it is easy to turn them into precise alignment so that they nest, as shown in FIGURE 2, ready for a subsequent operation.

In the modified form of the device shown in FIGURE 5, there is provided an exterior cylinder 112 having a primary separator 113 secured thereto and provided with a striking surface 114. Within the cylinder 112 a hollow piston 116 is reciprocable. The piston itself has a secondary separator 117 with its own striking surface 118. Normally, the primary and secondary separators are nested with the striking surfaces adjacent as shown in FIG- URE 5, so that they both can be simultaneously driven into a log to be split. In this instance, both the cylinder 112 and the piston 116 are away from hydraulic fluid and are grease lubricated.

To provide the actuating or expanding force, a hydraulic jack 119 is incorporated into the piston cylinder assembly. A standard hydraulic jack 119 is provided with a threaded portion 121 which engages a collar 122 secured to the cylinder 112. The plunger 123 of the jack 11? is connected by a pin 124 to a boss 126 secured to the secondary separator 117. Preferably the plunger 123 is flattened and fits within a bifurcated end 127 and tightly against the boss 126. The jack 11% is connected by a flexible conduit 131 to a hydraulic pump 132 having an actuating handle 133.

With this arrangement, the jack mechanism is positioned on a log to be split either by having the primary separator 113 and the secondary separator 117 driven into place or is positioned in a previously provided slot, for example, the back cut in a tree to be felled. The pump 132 is situated at any convenient adjacent location, and the handle 133 is actuated. The primary and secondary separators thus are urged apart by hydraulic pressure. This pressure increases and imposes an increasing strain on the engaged members until the split or motion occurs. The mechanism is then removed and is returned to initial position by forcing the plunger back into the jack manually after the manipulation of a valve 134 or by operating the handle 133 after reversing the valve 134.

In both forms of the invention there is provided a log splitter Which is effective to split a log or to move apart comparable elements under hydraulic pressure generated easily by an operator and under his control, there being provided adequate safeguards to prevent the mechanism from being overloaded or from over-travelling.

What is claimed is:

1. A log splitter comprising a hydraulic cylinder, a primary separator fixed on said cylinder and extending laterally therefrom, a hydraulic piston reciprocable in said cylinder and dividing said cylinder into a pressure chamber and a reservoir, :1 piston rod on said piston and extending from one end of said cylinder, a secondary laterally extending separator on said piston rod aligned with said primary separator, means for closing the other end of said cylinder, a pump in said closing means and connected to said reservoir and to said pressure chamber, and means for controlling the transfer of hydraulic fluid between said pressure chamber and said reservoir.

2. A log splitter comprising a hydraulic jack including a relatively movable cylinder and piston and extending laterally to one side thereof, a primary separator fixed on said cylinder, a secondary separator fixed on said piston, extending laterally thereof in alignment With said primary separator and movable into close proximity to said primary separator, a striking member secured to one of said separators on the other side of said cylinder and extending over and into substantial contact with an adjacent portion of the other of :said separators When said separators are in close proximity, means mounted on said cylinder for hydraulically moving said cylinder and piston to separate said primary and secondary separators, and means for inactivating said moving means.

References Cited in the file of this patent UNITED STATES PATENTS Schwarz Oct. 18, 1960 

